dpp-nfc: Start listen operation more completely for NFC Tag write cases

Share the same setup steps from the negotiated connection handover to
fix issues with NFC Tag write cases in AP mode. This addresses issues in
the AP mode DPP listen operation not actually receiving anything when
the write-a-tag code path was used.

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>

wpa_supplicant/examples/dpp-nfc.py

@@ -192,6 +192,31 @@ def dpp_bootstrap_gen(wpas, type="qrcode", chan=None, mac=None, info=None,
         raise Exception("Failed to generate bootstrapping info")
     return int(res)
 
+def dpp_start_listen(wpas, freq):
+    if get_status_field(wpas, "bssid[0]"):
+        summary("Own AP freq: %s MHz" % str(get_status_field(wpas, "freq")))
+        if get_status_field(wpas, "beacon_set", extra="DRIVER") is None:
+            summary("Enable beaconing to have radio ready for RX")
+            wpas.request("DISABLE")
+            wpas.request("SET start_disabled 0")
+            wpas.request("ENABLE")
+    cmd = "DPP_LISTEN %d" % freq
+    global enrollee_only
+    global configurator_only
+    if enrollee_only:
+        cmd += " role=enrollee"
+    elif configurator_only:
+        cmd += " role=configurator"
+    global netrole
+    if netrole:
+        cmd += " netrole=" + netrole
+    summary(cmd)
+    res = wpas.request(cmd)
+    if "OK" not in res:
+        summary("Failed to start DPP listen", color=C_RED)
+        return False
+    return True
+
 def wpas_get_nfc_uri(start_listen=True, pick_channel=False, chan_override=None):
     listen_freq = 2412
     wpas = wpas_connect()
@@ -221,13 +246,8 @@ def wpas_get_nfc_uri(start_listen=True, pick_channel=False, chan_override=None):
     if "FAIL" in res:
         return None
     if start_listen:
-        cmd = "DPP_LISTEN %d" % listen_freq
+        if not dpp_start_listen(wpas, listen_freq):
-        global netrole
+            raise Exception("Failed to start listen operation on %d MHz" % listen_freq)
-        if netrole:
-            cmd += " netrole=" + netrole
-        res2 = wpas.request(cmd)
-        if "OK" not in res2:
-            raise Exception("Failed to start listen operation (%s)" % cmd)
     return res
 
 def wpas_report_handover_req(uri):
@@ -673,24 +693,7 @@ class HandoverServer(nfc.handover.HandoverServer):
                         freq = 2437
                     else:
                         summary("Negotiated channel: %d MHz" % freq)
-                    if get_status_field(wpas, "bssid[0]"):
+                    if not dpp_start_listen(wpas, freq):
-                        summary("Own AP freq: %s MHz" % str(get_status_field(wpas, "freq")))
-                        if get_status_field(wpas, "beacon_set", extra="DRIVER") is None:
-                            summary("Enable beaconing to have radio ready for RX")
-                            wpas.request("DISABLE")
-                            wpas.request("SET start_disabled 0")
-                            wpas.request("ENABLE")
-                    cmd = "DPP_LISTEN %d" % freq
-                    global enrollee_only
-                    global configurator_only
-                    if enrollee_only:
-                        cmd += " role=enrollee"
-                    elif configurator_only:
-                        cmd += " role=configurator"
-                    summary(cmd)
-                    res = wpas.request(cmd)
-                    if "OK" not in res:
-                        summary("Failed to start DPP listen", color=C_RED)
                         break
 
                 carrier = ndef.Record('application/vnd.wfa.dpp', 'A', uri.data)